The invention relates to an electromagnetic switching relay. More particularly, the invention relates to an electromagnetic switching relay having guide elements that accurately align a magnetising coil with a base member to ensure proper spacing for an armature to interact with a switch contact.
Conventional electromagnetic switching relays have a base member on which a magnetising coil, a magnet core, a yoke and an armature are arranged. The armature interacts with a switch contact that is adjustable between a contact position in which the switch contact connects a first and a second terminal, and a release position in which the switch contact disconnects the first and the second terminal as a function of a current flowing through the magnetising coil. Electromagnetic switching relays of this type are known in the most varied of embodiments and are used, for example, in motor vehicle engineering. The known switching relays differ, in particular, with regard to the manner in which the mechanical relay parameters thereof are adjustable.
The described relays may comprise a magnetic bistable as well as a monostable magnetic circuit. Two switching positions with open and closed contacts are held by spring magnet or permanent magnet forces resulting from the insertion of a permanent magnet into the magnetic circuit. If the contacts are closed, the magnetic retention forces are generated by a permanent magnet in the bistable type or by the current-carrying coil in the monostable relay. The bistable magnetic circuit is weakened or strengthened by means of magnetic coils with opposite magnetic orientation, in order to obtain alternating switching positions. This is achieved by means of two coils with opposite windings or by electrical polar reversal.
One example of an electromagnetic relay having adjustable mechanical relay parameters is disclosed in DE 199 20 742 A1. DE 199 20 742 A1 teaches an electromagnetic relay having a base member, a magnet system and an armature spring. The magnet system has an armature on which two lever portions are formed constituting the support points for the armature spring. A further support point for the armature spring is located on a fixed relay portion. By bending the fixed relay portion the armature and, therefore, the contact spacing can be adjusted.
Because of unavoidable manufacturing tolerances, the spacing between the switch contact and the terminals does not correspond exactly to a desired value, but rather is subject to manufacturing-based variations. As a result, individual and generally manual adjustment of the contact spacing is required wherein, for example, either the magnet core is indented or a contact spring connected to the armature is bent. These known methods are time consuming and complex, and there is a risk that the adjusted contact spacing and overtravel will not remain constant, for example, owing to an elastic recovery from the plastic region of the contact spring.
It is therefore desirable to provide an electromagnetic switching relay that is simple in design and allows reliable and constant adjustment of contact spacing and overtravel for accurate arrangement of a magnetising coil with respect to the fixed contacts.
The invention relates to an electromagnetic switching relay having a base member and a magnetised coil. The base member having first guide elements. The magnetised coil having a terminal and second guide elements positioned substantially between the first guide elements that allow displacement of the magnetising coil relative to the base member and engage the first guide elements to fix the magnetising coil relative to the base member.
The invention further relates to a method for accurately arranging a magnetising coil in an electromagnetic switching relay. The magnetising coil is positioned relative to a base member by displacing the magnetising coil along first guide elements on either side of the base member and the magnetising coil. The magnetising coil is fixed relative to the base member by exerting a vertical pressure force on a partition layer by the magnetising coil or the base member.
An advantageous embodiment comprises a partition layer that is in one piece with a base member plate.
In a preferred embodiment the partition layer is incorporated at opposite longitudinal sides of a shaft. Preferably, the partition layer is a surrounding rim in a shaft of the base member plate.
In another preferred embodiment the guide elements have the shape of locking runners, whereby one locking runner comprises at least one longitudinal strut and one transversal strut.
Furthermore, it is advantageous to provide several transversal struts which are incorporated in opposite position at two longitudinal sides of the longitudinal strut.
The transversal struts preferably comprise a slanted plane which is inclined in an upward direction towards the longitudinal strut. The slanted plane allows for low-force locking between the transversal struts and the partition layer.